Bearings are necessary to provide aerodynamic guidance for missiles in their trajectory. The bearing assembly is secured in a guidance mechanism for an attack rocket. It is desirable that such bearing assemblies be lightweight yet provide maximum system stiffness at minimum rolling friction torque. However, optimized system stiffness and torque are fundamentally two opposing properties. Such an assembly must be able to handle loads, shock and vibration while maintaining a steady flight course and thereby requiring minimal power for any course adjustments/corrections during flight. The combination of lightweight, high stiffness and low torque has favorable cascading effects on most support hardware such as electric motors and other electro-optical components as they can be less bulky and lightweight as well. While a guidance mechanism may be stiffened using a multitude of bearings at greater cost and weight, hence requiring heavier motors and other components, one object of the present invention is to achieve maximum stiffness with fewer bearings, with reduced system weight thereby requiring less power to drive such a system.
The guidance mechanism typically is supported within the rocket by multiple pairs of angular contact ball bearings configured for use as a matched set and preloaded with a plurality of retainer nuts. In general, each angular contact ball bearing includes an inner member such as an inner housing, an outer member such as a housing, and a plurality of rolling elements disposed between the inner member and the outer member. In many applications, the plurality of rolling elements is separated by a plurality of spacers wherein typically a spacer is positioned between a pair of rolling elements. Such a pair of angular contact ball bearings is commonly referred to as a “duplexed” pair of bearings or a “duplex bearing.”